Changing Planet

Most Crowded Galaxy Discovered, Only 54 Million Light Years Away

Packed with an extraordinary number of stars, M60-UCD1 is an ultra-compact dwarf galaxy 54 million light years from Earth. It was discovered with NASA's Hubble Space Telescope and follow-up observations were done with NASA's Chandra X-ray Observatory and ground-based optical telescopes. Credit: X-ray: NASA/CXC/MSU/J.Strader et al, Optical: NASA/STScI
Packed with an extraordinary number of stars, M60-UCD1 (seen in the insert) is an ultra-compact dwarf galaxy 54 million light years from Earth residing near the giant elleptical galaxy M60. It was discovered with NASA’s Hubble Space Telescope and follow-up observations were done with NASA’s Chandra X-ray Observatory and ground-based optical telescopes. Credit: X-ray: NASA/CXC/MSU/J.Strader et al, Optical: NASA/STScI

Astronomers have discovered the densest galaxy ever seen, and at 54 million light years away, it’s in our galactic neighborhood.

Using the combined imaging capabilities of ground-based observatories with the high-flying Hubble Space Telescope and its cousin, the Chandra X-Ray Observatory, the ultra-compact dwarf galaxy known as M60-UCD1 turns out to be 15,000 times denser than what is found in our own galaxy, the Milky Way.

“Traveling from one star to another would be a lot easier in M60-UCD1 than it is in our galaxy, but it would still take hundreds of years using present technology,” said lead author of the new study, astronomer Michigan State University’s Jay Strader, in  a press release.

What’s even more remarkable about M60-USD1 is that the galaxy’s most crowded part–its core, where half its 200 million solar masses resides–spans a radius of only 80 light years. That means the stars in this little galaxy are about 25 times  closer to each other than those we find around the Sun’s galactic neighborhood.

Chandra observations have revealed that the galaxy’s tiny core harbors a strong x-ray source, which belongs to a giant black hole that weighs 10 million times the mass of our sun. That makes it about twice the size of the black hole in our own galaxy.

Astronomers theorize that a close encounter with a neighboring galaxy billions of years ago may have ripped away stars from M60-USD1 and may have led to the supermassive black hole pulling in the surviving stars close together.

“We think nearly all of the stars have been pulled away from the exterior of what once was a much bigger galaxy,” said co-author Duncan Forbes of Swinburne University in Australia in the press release.

“This leaves behind just the very dense nucleus of the former galaxy, and an overly massive black hole.”

Follow Andrew Fazekas, the Night Sky Guy, on Twitter and Facebook.

Andrew Fazekas, aka The Night Sky Guy, is a science writer, broadcaster, and lecturer who loves to share his passion for the wonders of the universe through all media. He is a regular contributor to National Geographic News and is the national cosmic correspondent for Canada’s Weather Network TV channel, space columnist for CBC Radio network, and a consultant for the Canadian Space Agency. As a member of the Royal Astronomical Society of Canada, Andrew has been observing the heavens from Montreal for over a quarter century and has never met a clear night sky he didn’t like.
  • Sunandan Konwer

    I am too much excited to know if there is any sign of life there in that Galaxy M60-USD1!!!!!!!

  • vineet

    We r so surprised 2 see the sizes & nos. Of galaxies,stars, solar system,blackhholes, Supernova there powers & distances r out of our thinking & we r speechless but we took the god, Allah, Bhagwan or the master of this creation as granted. Think once about him who is everywhere then u can realize the greatness & merciness. So try to know. the creator not the creation. jay shrI Krishna.

  • varsha rathore

    i just wanna want to see this stars,galaxies,solar systems,black holes,,near to the eyes without seeing near they are looking so cute while seeing they will look so fabrious

  • varsha rathore

    they are looking so fabrious & cute

  • Poornima

    Amazing !!!!!!! let us try to more…….it make the scientists and developing young ones to study about space..making curious to know more abt t

  • George

    Small…. far away … small … far away…

  • byron

    What if our proximity and existences of black holes means something more? I wonder what the original substance of this galaxy included and held. Hmm.

  • Michael Haskins

    The creator: Gravity – “him who is everywhere” Thanks, Isaac Newton, Johannes Kepler, Edwin Hubble, Albert Einstein etc. for helping us to understand. Still, it IS AMAZING!

  • Cristian

    Maybe that galaxy no longer exists, becouse its lights come with a 54 million light years delay…

  • arunviggness

    its really ammizing……a humble newsssss

  • arunviggness

    wow….awsome……..its humble newssss

  • Yojan Uerupter

    The tiny remnants of the galactic dynamo that is the dog stars bone does not equate to the overall chemistry and composition of the entropic properties of this fabrious place in our neck of the woods. If the heat index is as much as the down in the universal comforter then the full spectrum of nothing must exist where life could be exposed.

  • Krishna

    This is always amazing. Thanks to all the scientists who spent their lives for providing humanity with this knowledge. Galaxy and even beyond is now the limit in the future. Or perhaps it is going to be limitless.

    Wish I was born a century later so that I understood all this in more details.

  • josh

    That is great to explore the universe. I wonder if there is life.

  • Khalidibrahim-alaaber

    The amazing action is fantastic beautiful magician

  • Khalidibrahim-alaaber

    O god to perfect your creation to master your mad
    Great made by the most grition

  • Bill Alexander

    Very interesting. If the stars are moving ever closer to the central black hole over time, then as they continue to do so I would expect some real fireworks as stars begin to eventually collide with one another, and the black hole devours more and more of its host galaxy’s stars. The galaxy would continue to spiral inward, creating copious outputs of GRBs among other interesting phenomena. What would galactic evolution models indicate for this galaxy’s future? That would be fascinating to answer. Certainly doesn’t sound like a very habitable place, I wonder if there is life and/or civilizations barely hanging on…

  • kitty

    future is going to be full of surprizes . and no matter when we are born there will always be something new after we are gone -its wonderful to know what we know now than before when moon was cheese ….thanks to all scientists and their think tanks

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